Self-inking stamp



(No Model.)

C. S. BURTON. SELF INKING STAMP.

Patented Mar. 3 1, 1891.

NITED STATES PATENT EEicE.

CHARLES S. BURTON, OF CHICAGO, ILLINOIS.

SELFINKING STAMP.

SPECIFICATION forming part of Letters Patent o. 449,309, dated March 31,1891. Application led November 26, 1886. Serial No. 219,959. (No model.)

To all whom it may concern:

.Be it known that I, CHARLES S. BURTON, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Self-Inking Stamps,which are fully set forth in the following specification, referencebeing had to the accompanying drawings, forming a part thereof, where-111- Figure l is a transverse vertical section showing thestamp closed,the ink-pad in contact with the printing-face section being made at theline a' on Fig. 4. Fig. 2 is a section at the same plane, showing thedie depressed, as at the instant of imprinting. Fig. 3 is a section atthe same plane, showing the die partly depressed and the ink-pad inposition to actuate it upward. Fig. 4 is a side elevation, thepartsbeing'in the position of Fig. 1. Fig. 5 is a section similar toFig. l showing only a single ink-pad. Figli is a plan of the blank fromwhich the frame is made. Fig.-7 is a plan of 'the blank from which thedieholder is made. Fig. 8 is a plan of the blank from which each of thepad-holders is made.

A is the frame.

B is the die-holder or plunger.

C is the ink-pad holder.

D is a shaft on which the ink-pad holder is pivoted.

E is a spring,which is coiled about the shaft D and operates the ink-padholder, causing it to fold up against the die, and in so doing to forcethe latter and the die-holder upward in the frame.

F is the die or stamp containing the printing-face.

G is the ink-pad.

The frame A has guide grooves or slots a a for the die-holder B, and thelatter has the projections ZJ b at the ends to iit and slide in saidgrooves or slots. The frame A also' has any convenient means for guidingthe die-holder at the middle. As these parts are constructed, thedie-holder has the inverted U-shaped stem B', which strides thecross-bar A of the frame, and the latter has the notches a a', in whichthe arms of said stem B rest and slide, being'guided thereby. Theguiding of the die-holder inthe frame may be accomplished in many otherfamiliar ways. The method Vhereinabove described, however, enables me tomake the device very cheaply and of few pieces, as hereinafter morefully set forth. i The ink-pad holder C is pivoted on the shaft D, sothat the plane of its inked surface-the plane at which the die comesinto contact with it-passesthrough the axis of the said shaft. While itis not absolutely essential that this rule of construction be rigidlyobserved in the case of the narrow dies,

it must be approximately followed, and in wide dies, the approximationmust be quite close in order to effect the purpose, which is to avoidthe necessity for any movement of the ink-pad in order to clear the diebefore the latter begins to `descend or to come into contact after ithas risen. If the pivot of the ink-pad were in a different plane fromthe inking-surface of the pad which is'in contact with theprinting-surface of the die, the simultaneous commencement of themovement of both die and pad would cause the inking-surface to slideover a portion of the die-surfaceon the edge toward the pivot and smearthe printing-face of that part while it is swinging up toward the planeof the face, and there will also be a liability that the more remoteportion of the printingface will not be brought into contact with thepad and will not receive ink. WVhen, however, the pivot of thepad-holder is in the plane of the inking-surface, the two surfaces-theinking-surfaceand the printingsurface-separate like the'leaves of ahinge, the movement of the inking-surface at the first instant ofseparation being at right angles to the printing-face, so that the die,descending at the same instant, moving also at right angles to its ownprinting-face, becomes yseparated from the pad only by virtue of itsslower movement, the separation being as direct as if it had remainedstationary and only the pad had moved.

The ink-pad holder is forced and held upward by the spring, which ispreferably coiled around its shaft D and stopped against the frame A atthe ends, and against the padholder at the middle part, where it isprovided with the loop E for that purpose, being preferably coiled inopposite directions from that loop. Y It is forced downward by theengage ment of the die-holder upon its upraised rims IOO or flanges c2c2 at the ends, the die-holder descending, sliding along said flanges,and so swinging the pad-holder downward and outward. In order that thismovement should' be possible, the pivot of the pad-holder must beoutward from the vertical plane of the edge of the die-holder, whichthus engages the flanges, and being thus located, the nearer edge of theprinting-face in the die-holder being necessarily a little farther fromsaid pivot than the engaging and actuating edge of the flange c2, themovement of the part of the pad in contact with said nearer edge of theprinting-face is more rapid because farther from the pivot than that ofthe die-face in Contact with it, since said die-face descends directlyand no point moves any faster than the actuating-edge e2.

The die-holder is returned upward after the impression is made by theaction of the padholder by the force of the spring E. Ordinarily theedge of the die-holder is far enough inward from the vertical plane ofthe pivot of the pad-holder, so that the edge of the flange c2 of thelatter at the lowest position of the die is sufficiently inclined toadapt it to start the die upward, and as it moves up the angle of theengagement between the parts improves--that is, the angle between theactuating-edge of the flange b2-and the vertical line of movement of thedie increases, and the purchase of the actuating part against theactuated part increases, so that the movement, once started, is certainto continue until the die and pad are restored to their initialposition; but in some cases I find it desirable to locate thepivot-shaft E so near the vertical plane of the edge of the die-holderthat the angle between them when the die is down is so acute that theholder cannot start the die up, and in that case I provide the lug ortooth 010, projecting most conveniently from the edge of the flange c ofthe pad-holder, and made of such length that when the pad-holder isswung down to the lowest point the said lug will project inward to thevertical plane of some part of the descending die-holder, so that it mayengage the same. As shown constructed in the drawings, the mostconvenient part to adapt for this purpose is the stem b', and it isadapted to be engaged by the tooth cw by being provided with the slothw, into which the tooth c10 passes as the pad-holder swingsand as thedie-holder descends the slot terminates at such point that its upperboundary comes into contact with the tooth before the dieholder reachesthe lowest point, and when the die-holder is relieved of the pressure ofthe hand of the operator the pad-holder, actuated by the spring E,causes the tooth cw to actuate the die-holder and start it upward,-andbefore the said tooth passes clear of the slot the die-holder has risenso far that the edge of the flange c2 engages it at a sufficient ang-1eto actuate it the remaining distance, as first above described.

lVhen the die is of considerable width, I prefer to provide twopad-holders pivoted one on each side and covering each one-half of thedie, as shown in the drawings. By this means the height of the entiredevice is much reduced, because the stroke of the die, which isnecessarily as great as the width of the padholder, is reduced one-half.The advantages of this construction over others hitherto in use are thegreater compactness and greatly diminished height, and these advantagesare attained by three principal features: first, pivoting the pad-holderapproximately in the plane of the inking-surface, whereby thepreparatory and final movement of the die are rendered unnecessary;second, locating the actuating-spring about the horizontal shaft of itspad-holder instead of in or about the vertical stem of the die-holderand using therefore a torsion instead of acompression spring, sincey theuse of the latter involves telescoping the handle and giving it when notin use a length at least double the stroke it is to make; third,dividing the pad -holder into halves, and thereby dividing its stroke bytwo.

In the common form of plunger self-inking stamps the entire height isnecessarily more than three times the length of the stroke, and thelength of the stroke is necessarily from one-fifth to one-third greaterthan the width of the die, whereby the height becomes from five to eighttimes the width of the die.

By embodying in my construction the three features above mentioned I amable to make the entire height not to exceed double the width of thedie.

I claiml. In combination with the frame, the inkpad holder pivoted tothe frame, the axis of its pivot being horizontal, a spring which ICOactuates the pad-holder to rock it about its pivot, and the die-holderreciprocating vertically in the frame and operated upwardly by theink-pad holder, substantially as set forth.

2. In combination with the frame, the inkpad holder pivoted thereto androcked about a horizontal axis, the die-holder reciprocating verticallyin the frame past the axis of the pad-holder, a spring actuating thepad-holder and rocking it about its pivot, the pad-holder having aflange c2, which engages the edge of the die-holder, the distance of thepivot of the pad-holder from the path of reciprocation of the proximateedge of the die-holder being greater than the width of the flange,whereby the spring which actuates the pad-holder through said pad-holderactuates the dieholder, substantially as set forth.

3. In combination with the frame and the die-holder reciprocatingtherein, the ink-pad holder pivoted to the frame and swinging up againstthe printing-face of the die and having a projection, as the tooth cw,at an angle with the inking-surface engaging the dieholder,substantially as and for the purpose set forth.

4. In combination with the frame and the i die-holder reciprocatingtherein, the two inkpad holders pivoted on opposite'sides of theWashington, District of Columbia, this 26th path of reoiprocation of thedie-holder and day of November, A. D. 1886. folding 11p against theprinting-face of the die and meeting edge to edge, substantially CHAS.S. BURTON. 5 as set forth. Witnesses:

In testimony whereof I have hereunto set i REX SMITH,

my hand, in the presence of two Witnesses, at l A. M. SMITH.

